Constellation -- Whenever Agent of Erebos or another enchantment enters the battlefield under your control, exile target player's graveyard.

Akoum Refuge enters the battlefield tapped.

When Akoum Refuge enters the battlefield, you gain 1 life.

{T}: Add {B} or {R}.

Remove a +1/+1 counter from Arcbound Reclaimer: Put target artifact card from your graveyard on top of your library.

Modular 2 (This creature enters the battlefield with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

{1}{R}, Sacrifice a Goblin: Arms Dealer deals 4 damage to target creature.

{T}: Add {C}.

Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Sacrifice a creature: Add {C}{C}.

Haste

Echo {3}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)

When Avalanche Riders enters the battlefield, destroy target land.

Whenever a creature dies, put a charge counter on Black Market.

At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

Bojuka Bog enters the battlefield tapped.

When Bojuka Bog enters the battlefield, exile target player's graveyard.

{T}: Add {B}.

{T}: Add {C}.

{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Discard a card: You may cast a creature spell from your graveyard this turn. Activate only once each turn.

Whenever a nontoken creature enters the battlefield under your control, if you didn't cast it from your hand, it gains haste until your next turn.

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

{T}: Add one mana of any color in your commander's color identity.

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Whenever you tap a Swamp for mana, add an additional {B}.

Whenever another creature dies, you may put a +1/+1 counter on Deathbringer Thoctar.

Remove a +1/+1 counter from Deathbringer Thoctar: It deals 1 damage to any target.

Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain.

{T}: Add {B} or {R}.

Return target creature card from your graveyard to the battlefield.

Flashback--Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

{2}: Put target card from your graveyard on the bottom of your library.

Whenever Goblin Assassin or another Goblin enters the battlefield, each player flips a coin. Each player whose coin comes up tails sacrifices a creature.

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

When Goblin Matron enters the battlefield, you may search your library for a Goblin card, reveal that card, put it into your hand, then shuffle.

When Goblin Recruiter enters the battlefield, search your library for any number of Goblin cards, reveal them, then shuffle and put those cards on top in any order.

Goblin Sharpshooter doesn't untap during your untap step.

Whenever a creature dies, untap Goblin Sharpshooter.

{T}: Goblin Sharpshooter deals 1 damage to any target.

Other Goblins you control get +1/+1.

Sacrifice a Goblin: Destroy target artifact.

Deathtouch

When Gonti, Lord of Luxury enters the battlefield, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast it.

When Gray Merchant of Asphodel enters the battlefield, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Grenzo, Dungeon Warden enters the battlefield with X +1/+1 counters on it.

{2}: Put the bottom card of your library into your graveyard. If it's a creature card with power less than or equal to Grenzo's power, put it onto the battlefield.

Whenever a creature you control deals combat damage to a player, choose one --

• Goad target creature that player controls.

• Exile the top card of that player's library. Until end of turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Morph {B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Whenever another nontoken creature you control dies, draw a card.

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

{T}: Add {R}.

Defender

{T}: Put target card from a graveyard on the bottom of its owner's library.

Haste

{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

{T}: Create X 1/1 red Goblin creature tokens, where X is the number of Goblins you control.

{T}: Add {B}.

Champion a Goblin or Shaman (When this enters the battlefield, sacrifice it unless you exile another Goblin or Shaman you control. When this leaves the battlefield, that card returns to the battlefield.)

{T}: Lightning Crafter deals 3 damage to any target.

Other Goblin creatures you control get +1/+1.

{T}: Regenerate another target Goblin.

Whenever a player sacrifices a permanent, Mayhem Devil deals 1 damage to any target.

As Metallic Mimic enters the battlefield, choose a creature type.

Metallic Mimic is the chosen type in addition to its other types.

Each other creature you control of the chosen type enters the battlefield with an additional +1/+1 counter on it.

When Meteor Golem enters the battlefield, destroy target nonland permanent an opponent controls.

Echo {1}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)

When Mogg War Marshal enters the battlefield or dies, create a 1/1 red Goblin creature token.

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

When Murderous Redcap enters the battlefield, it deals damage equal to its power to any target.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

{T}: Add {C}{C}.

Whenever Pawn of Ulamog or another nontoken creature you control dies, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

When Phyrexian Delver enters the battlefield, return target creature card from your graveyard to the battlefield. You lose life equal to that card's mana value.

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

When Plaguecrafter enters the battlefield, each player sacrifices a creature or planeswalker. Each player who can't discards a card.

When Priest of Gix enters the battlefield, add {B}{B}{B}.

When Priest of Urabrask enters the battlefield, add {R}{R}{R}.

Flying

When Puppeteer Clique enters the battlefield, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Rakdos Carnarium enters the battlefield tapped.

When Rakdos Carnarium enters the battlefield, return a land you control to its owner's hand.

{T}: Add {B}{R}.

When Ravenous Chupacabra enters the battlefield, destroy target creature an opponent controls.

{3}: Put target card from a graveyard on the bottom of its owner's library.

When Siege-Gang Commander enters the battlefield, create three 1/1 red Goblin creature tokens.

{1}{R}, Sacrifice a Goblin: Siege-Gang Commander deals 2 damage to any target.

Protection from red

Tap five untapped Goblins you control: Skirk Fire Marshal deals 10 damage to each creature and each player.

Sacrifice a Goblin: Add {R}.

When Sling-Gang Lieutenant enters the battlefield, create two 1/1 red Goblin creature tokens.

Sacrifice a Goblin: Target player loses 1 life and you gain 1 life.

{T}: Add {C}{C}.

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

When Solemn Simulacrum dies, you may draw a card.

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)

Spinerock Knoll enters the battlefield tapped.

{T}: Add {R}.

{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

{T}: Add {C}.

{T}: Add {B} or {R}. Activate only if you control a Swamp.

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

{T}: Put target permanent you own on the bottom of your library.

This spell costs {2} less to cast for each creature card in your graveyard.

Whenever a creature you control dies, put it on the bottom of its owner's library.

{2}{B}, {T}, Pay 2 life: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Equipped creature has "{2}, {T}: This creature deals 1 damage to any target" and "Whenever a creature dies, untap this creature."

Whenever a Shaman creature enters the battlefield, you may attach Thornbite Staff to it.

Equip {4}

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Pay 3 life: Add {R}.

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

When Woe Strider enters the battlefield, create a 0/1 white Goat creature token.

Sacrifice another creature: Scry 1.

Escape--{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Woe Strider escapes with two +1/+1 counters on it.

Workhorse enters the battlefield with four +1/+1 counters on it.

Remove a +1/+1 counter from Workhorse: Add {C}.

Haste

Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.

Sacrifice another creature: Yahenni gains indestructible until end of turn.

Haste

When Zealous Conscripts enters the battlefield, gain control of target permanent until end of turn. Untap that permanent. It gains haste until end of turn.

When Zhalfirin Void enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

{T}: Add {C}.

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.